The present invention concerns containers utilized to house liquids and, more specifically, to containers utilized to house liquid ink for inkjet printer applications. Ink containers may be integral with a printhead or communicatively connected thereto. In applications where replacement ink containers are communicatively connected to a permanent printhead, it is desirable that the container be able to supply ink in a predictable manner. Exemplary replacement ink containers may includes one or more chambers filled or partially occupied by liquid ink. To impart a predictable flow of ink from the container to the printhead, the container may house one or more backpressure mediums. Backpressure mediums are mediums that include pores through which liquids can flow, but that provide a resistance to flow resulting from capillary action. Typical backpressure mediums include felts, foams, and other fibrous mediums having pores sizes imparting predictable resistance to fluid flow from the resulting capillarity.
In order to increase the utilization of ink within a container, it is usually preferred that the backpressure medium occupy as little space as possible to satisfy the breathing requirements of the container. At the same time, less backpressure medium results in less control over the flow of ink from the container. In other words, a balance is generally arrived at that involves providing one chamber of the container having a backpressure medium (backpressure chamber) that is in communication with another chamber of the container housing only liquid ink or a combination of liquid ink and trapped gases (free ink chamber).
Conventional ink containers provide for transfer of liquid ink between free ink chambers and backpressure chambers using one or more openings through internal walls of the container that would otherwise separate the chambers. Typically, one or more internal walls step as a partition, but for an opening through the lower level of the wall to allow ink to travel from the free ink chamber and into the backpressure chamber only when the level of ink within the backpressure chamber drops below a predetermined point. This predetermined point typically coincides with the level of the opening between the chambers so that air bubbles from the backpressure chamber can flow into the free ink chamber to displace liquid ink, thereby driving liquid ink into the backpressure chamber until the level of ink within the backpressure chamber rises and cuts off the opening, discontinuing gaseous transfer into the free ink chamber and liquid ink transfer into the backpressure chamber.
Some embodiments of the instant invention provide an alternative to the internal wall openings and provides conduits that extend outside of the conventional ink container by utilizing a substrate mounted to the exteriors of the chambers that allow communication between the free ink chamber and the backpressure chamber, with or without requiring molding of openings within internal walls. Some embodiments also provide manufacturing alternatives that allow the formation of openings within the internal wall separating the chambers without requiring tooling to be substantially constrained by the dimensions of the ink container.
Some embodiments of the present invention to provide a method of forming a conduit providing fluid communication between respective reservoirs of an ink tank, that include the steps of: (a) forming a first orifice extending through a first external wall portion of an ink tank defining part of a first ink reservoir of the ink tank; (b) forming a second orifice extending through a second external wall portion of the ink tank defining part of a second ink reservoir of the ink tank; and (c) attaching a substrate over the first and second external wall portions at least about a first continuous seal line surrounding both the first and second orifices to define an external conduit communicatively connecting the first ink reservoir with the second ink reservoir.
In an embodiment, the method further includes the step of providing at least one depression in the first and second external wall portions extending between the first and second conduits. In another embodiment, the method further includes the steps of (i) forming a third orifice extending through a third external wall portion of the ink tank defining part of the first ink reservoir; (ii) forming a fourth orifice extending through a fourth external wall portion of the ink tank defining part of the second ink reservoir; and (iii) attaching a second substrate over the third and fourth external wall portions at least about a second continuous seal line surrounding both the third and fourth orifices to define a second external conduit communicatively connecting the first ink reservoir with the second ink reservoir. In a further embodiment, the first orifice is adjacent to a first felt member occupying at least a portion of an internal area of the first ink reservoir, and the second orifice is in direct communication with free ink occupying at least a portion of an internal area of the second ink reservoir.
In yet another embodiment, the first and second substrates include a single substrate and the single substrate comprises the first and second seal lines. In still another more detailed embodiment, the first orifice and the second orifice of the first ink reservoir are adjacent to a first felt member occupying at least a portion of an internal area of the first ink reservoir, the first orifice and the second orifice of the second ink reservoir are in direct communication with free ink occupying at least a portion of an internal area of the second ink reservoir, and the combination of the first conduit and the second conduit provides the exclusive manner for fluids to traverse between the first reservoir and the second reservoir. In a further embodiment, the substrate comprises a polymer film, and the first portion of the film is laminated to an exterior wall of the first ink reservoir and to an exterior wall of the second ink reservoir. In still a further detailed embodiment, the step of laminating the first portion of the substrate to the first ink reservoir and to the second ink reservoir includes at least one of heat staking, laser welding, ultrasonic welding, vibrational welding, and adhesive mounting a film to an exterior wall of the first ink reservoir and to an exterior wall of the second ink reservoir.
Some embodiments described herein include a method of forming a conduit providing fluid communication between respective reservoirs of an ink tank, the method comprising the steps of: (a) forming a first orifice through a wall of an ink tank and into communication with a first reservoir and a second reservoir of the ink tank; and (b) sealing a substrate to the ink tank to overlap the first orifice and form a first by-pass conduit communicatively connecting the first reservoir and the second reservoir.
In a more detailed embodiment, the method further includes the steps of: (i) forming a second orifice through the wall of the ink tank and into communication with the first reservoir and the second reservoir of the ink tank; and (ii) sealing the substrate to the ink tank to overlap the second orifice and form a second by-pass conduit communicatively connecting the first reservoir and the second reservoir. In yet another more detailed embodiment, the first reservoir comprises a free ink reservoir, and the second reservoir comprises a backpressure reservoir that is occupied by a backpressure media. In a further detailed embodiment, the combination of the first conduit and the second conduit provides the exclusive manner for fluids to traverse between the first reservoir and the second reservoirs and the substrate comprises a polymer film.
Some embodiments of the present invention provide an ink tank comprising: (a) a first reservoir for housing a liquid ink, the first reservoir including a first orifice through a wall at least partially defining an interior region of the first reservoir; (b) a second ink reservoir for housing a liquid ink, the second ink reservoir including a first orifice through a wall at least partially defining an interior region of the second reservoir; and (c) a first conduit overlapping the first orifice of the first ink reservoir and the first orifice of the second ink reservoir allowing fluid communication between the first reservoir and the second reservoir, the first conduit defined at least in part by a film mounted to the wall of the first ink reservoir and to the wall of the second ink reservoir.
In a more detailed embodiment, the first reservoir comprises a backpressure chamber housing at least one backpressure medium through which liquid ink traverses prior to exiting through an ink outlet orifice of the backpressure chamber, and the second reservoir comprises a free ink chamber housing liquid ink prior to entering the backpressure chamber. In yet another more detailed embodiment, the free ink chamber and the backpressure chamber share a common wall, and the common wall includes an opening therethrough providing a second conduit between the free ink chamber and the backpressure chamber. In a further detailed embodiment, at least one of the wall of the first reservoir and the wall of the second reservoir includes a furrow extending lengthwise in parallel with a line of travel between the first orifices. In still a further detailed embodiment, the ink tank further comprises: (i) a second orifice through the wall at least partially defining the interior region of the first reservoir; (ii) a second orifice through the wall at least partially defining the interior region of the second reservoir; and (iii) a second conduit overlapping the second orifice of the first ink reservoir and the second orifice of the second ink reservoir to allow fluid communication between the second orifices, the second conduit defined at least in part by a film mounted to the wall of the first ink reservoir and to the wall of the second ink reservoir.
Some embodiments of the present invention provide an ink tank comprising: (a) a first vessel defining a first ink reservoir; (b) a second vessel defining a second ink reservoir; and (c) a first by-pass conduit communicatively connecting the first vessel to the second vessel by way of a first orifice that concurrently exposes the first vessel and the second vessel, the first by-pass conduit comprising a first substrate overlapping the first orifice and enclosing one side of the first orifice to allow sealed fluid communication between the first vessel and the second vessel.
In a more detailed embodiment, the first reservoir comprises a free ink reservoir for supplying liquid ink to the second reservoir, and the second reservoir comprises a backpressure reservoir housing at least one backpressure medium through which liquid ink traverses prior to exiting through an ink outlet orifice of the second vessel. In yet another more detailed embodiment, the first vessel and the second vessel share a common wall that includes an opening therethrough directly linking the first reservoir to the second reservoir. In a further detailed embodiment, the ink tank further comprises a second by-pass conduit communicatively connecting the first vessel to the second vessel by way of a second orifice that concurrently exposes the first vessel and the second vessel. In still a further detailed embodiment, the second by-pass conduit comprises a separate substrate overlapping the second orifice and enclosing one side of the second orifice to allow sealed fluid communication between the first vessel and the second vessel. In a more detailed embodiment, the ink tank further comprises a second by-pass conduit communicatively connecting the first vessel to the second vessel by way of corresponding orifices that expose the first vessel and the second vessel, the second by-pass conduit comprising a second substrate overlapping the corresponding orifices and enclosing a side of the corresponding orifices to allow sealed fluid communication between the first vessel and the second vessel. In a more detailed embodiment, the first substrate and the second substrate comprise a polymer film.
Some embodiments of the present invention provide a method of facilitating fluid communication between chambers of an ink tank, the method comprising the steps of: (a) forming a hole through an exterior wall bounding a first chamber of an ink tank; (b) forming a hole through an exterior wall bounding a second chamber of an ink tank; and (c) sealing a film to the exterior wall of the first chamber and to the exterior wall of the second chamber to encompass the hole of the first chamber and the hole of the second chamber to create an external sealed conduit providing fluid communication between the first chamber and the second chamber.
Some embodiments of the present invention provide a method of establishing countercurrent fluid transfer between areas of an ink tank, the method comprising the step of sealing a film to an exterior surface of an ink tank to define a first sealed exterior passage between at least two compartments of the ink tank, the seal between the film and the exterior surface of the ink tank outlining at least a first opening through the ink tank.
In a more detailed embodiment, the method further comprises the step of sealing a second film to the exterior surface of the ink tank to define a second sealed exterior passage between at least two compartments of the ink tank, the seal between the film and the exterior surface of the ink tank outlining at least a second opening through the ink tank. In yet another more detailed embodiment, the step of sealing the second film to the exterior surface of the ink tank seals the second sealed exterior passage to the exclusion of the first sealed exterior passage. In a further detailed embodiment, the ink tank includes an interior passage through an interior wall of the ink tank providing fluid communication between the first chamber and the second chamber of the ink tank, where the interior passage allows fluid to flow in a first direction from the first chamber to the second chamber, and the first sealed exterior passage allows fluid to flow in a second direction, opposite that of the first direction.
Some embodiments of the present invention provide a method of forming an ink tank, the method comprising: (a) molding at least two ink chambers of an ink tank, each ink chamber is defined by vertical walls that intersect a horizontal wall, where the at least two chambers share a common wall dividing the chambers from one another; (b) forming a first orifice and a second orifice through the horizontal floor, where the second orifice is vertically overlapped by the common wall; (c) mounting a lid to the vertical walls opposite the horizontal wall; and (d) mounting a film over the first orifice and the second orifice to inhibit fluid from egressing through the orifices.
In a more detailed embodiment, the common wall includes an opening therethrough providing fluid communication between the at least two chambers, and the step of forming the second orifice through the horizontal wall includes removing material from the horizontal wall to create the second orifice and further includes removing material from the common wall directly above the second orifice to form the opening through the common wall. In a further detailed embodiment, further comprising the step of: (i) forming a first orifice through a vertical wall defining the first chamber; (ii) forming a first orifice through a vertical wall defining the second chamber; and (iii) mounting a film to the vertical wall of the first chamber and to the vertical wall of the second chamber to encompass the first orifices and provide a sealed conduit between the first chamber and the second chamber.